Absorbent articles of the kind that is worn inside ordinary underpants include incontinence shields and sanitary napkins. As these articles have to be sized and configured to fit in the limited space available in the crotch portion of the underwear, the articles are by necessity designed with a relatively small width. For this reason, a particular problem with such articles is that they may leak at the side edges, before the full absorption capacity of the article has been utilized.
Side leakage may occur as a consequence of absorbed fluid being dispersed equally fast in all directions from the point where the fluid enters the article. This will lead to the fluid escaping the article at the side edges before being distributed to the end portions of the article. Another cause of side leakage may be when the intake capacity of the article is insufficient to allow all fluid that is exuded onto the article to directly enter inside the article. Instead, the fluid will flow on the topsheet and out over the side edges of the article where it can leak out and soil the wearer's clothing. A further drawback when fluid flows on the outside of the topsheet is that a large portion of the body-contacting topsheet will be wet. This is of course highly undesirable as it makes the article unhygienic and unpleasant to wear.
Incontinence shields and sanitary napkins are designed to have a total absorption capacity that is large enough to absorb all fluid that is expected to be released to the absorbent article during a period of wear. However, the fluid is normally not exuded in a steady flow but as sudden gushes of relatively large volume under high pressure and during a very short time period. Accordingly, it would be desirable if the absorbent article was able to receive and contain the emitted fluid with corresponding speed.
Great efforts have been made in the past in order to overcome the side leakage problem in relation to disposable absorbent articles such as incontinence shields and sanitary napkins. However, to date no such effort has been completely successful.
International publication WO 2009/105000 discloses a laminate fibrous web having recesses with a diminishing cross-sectional area in a thickness direction of the web. The web can be used as a fluid intake material and is taught to improve fluid flow through the web.
Although the prior art laminate material may alleviate the side leakage problem to some extent, there is still a great need for further improvements of the side leakage security for the kind of absorbent article that is worn in the crotch portion of an undergarment.